Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 45
Filtrar
1.
Arq. bras. med. vet. zootec ; 68(3): 702-708, tab
Artículo en Inglés | LILACS, VETINDEX | ID: lil-785694

RESUMEN

The main goal of modern intensive fish farms should be to increase productivity at a low cost. The automation of fish feeding plays an important role in this scenario since it may improve feed efficiency and reduce organic waste emissions. The aim of this experiment was to provide basic information for the development of feeding techniques using automatic feeders. The experiment was done from September to December, with tilapia weighing 185g, fed 48 meals a day at 22 or 30 minute intervals, with feeding rates of 2, 3 and 4% of live weight. Eighteen 1m3 net cages equipped with automatic feeders were distributed in one pond. During the experimental trial the mean values for dissolved oxygen, pH and temperature were 3.20mg/l, 8.03 and 25.43°C, respectively. The highest average weight of 683.73g was achieved for fish treated with 4% of live weight at 30 minute intervals between meals. There was no difference for viscero-somatic index, demonstrating no alteration in the final carcass quality. These results demonstrate that a higher feeding rate added to efficient feed management can be used at the final stages of raising Nile tilapia in cages without compromising final fish productive quality.(AU)


O principal objetivo da criação intensiva de peixes deve ser o aumento da produtividade com baixos custos. Automação da alimentação tem papel importante nesse cenário, uma vez que melhora a eficiência alimentar e reduz a emissão de lixo orgânico. O objetivo deste experimento foi produzir informação básica para o desenvolvimento de tecnologia alimentar mediante o uso de alimentadores automáticos. O experimento foi realizado de setembro a dezembro, com tilápias pesando 185g e alimentadas 48 vezes ao dia, em intervalos de 22 ou 30 minutos, com taxa de alimentação de 2, 3 e 4% do peso vivo. Dezoito tanques-rede de 1m3 foram equipados com alimentadores automáticos e distribuídos em um lago. Durante o experimento, a média de oxigênio dissolvido, a de pH e a de temperatura foram 3,20mg/L, 8.03 e 25,43°C, respectivamente. A maior média de peso de 683,73g foi obtida para os peixes tratados com 4% do peso vivo e intervalo de 30 minutos entre as refeições. Não houve diferença no índice víscero-somático, o que demonstra a mesma qualidade final da carcaça. Esses resultados mostram que a alta taxa de alimentação, associada ao eficiente manejo alimentar, pode ser usada nos estágios finais de produção de tilápia-do-nilo em tanques-rede, sem comprometer a qualidade do produto final.(AU)


Asunto(s)
Animales , Alimentación Animal/análisis , Alimentación Animal/estadística & datos numéricos , Cíclidos/crecimiento & desarrollo , Conducta Alimentaria , Estanques/análisis , Peces , Alimentos Marinos/análisis
2.
Sci Rep ; 6: 25661, 2016 05 23.
Artículo en Inglés | MEDLINE | ID: mdl-27210416

RESUMEN

Atmospheric CO at Egham in SE England has shown a marked and progressive decline since 1997, following adoption of strict controls on emissions. The Egham site is uniquely positioned to allow both assessment and comparison of 'clean Atlantic background' air and CO-enriched air downwind from the London conurbation. The decline is strongest (approximately 50 ppb per year) in the 1997-2003 period but continues post 2003. A 'local CO increment' can be identified as the residual after subtraction of contemporary background Atlantic CO mixing ratios from measured values at Egham. This increment, which is primarily from regional sources (during anticyclonic or northerly winds) or from the European continent (with easterly air mass origins), has significant seasonality, but overall has declined steadily since 1997. On many days of the year CO measured at Egham is now not far above Atlantic background levels measured at Mace Head (Ireland). The results are consistent with MOPITT satellite observations and 'bottom-up' inventory results. Comparison with urban and regional background CO mixing ratios in Hong Kong demonstrates the importance of regional, as opposed to local reduction of CO emission. The Egham record implies that controls on emissions subsequent to legislation have been extremely successful in the UK.

3.
Cardiovasc Intervent Radiol ; 38(6): 1663-9, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26017456

RESUMEN

Refractory ascites (RA) is thought to complicate the postoperative course of 5-7% (Nishida et al. in Am J Transplant. 6: 140-149, 2006; Gotthardt et al. in Ann Transplant. 18: 378-383, 2013) of liver transplant recipients. RA after liver transplantation is often a frustrating diagnostic dilemma with few good management options unless an obvious mechanical factor is identified. Supportive therapies often fail until a treatable precipitating cause is identified and removed. We describe two patients who developed RA following liver transplantation for primary sclerosing cholangitis, and hepatitis C and alcoholic liver disease, respectively. The cause for RA was hyperkinetic portal hypertension secondary to splenomegaly in the first case and a pancreatic AVM in the 2nd case. After failure of other interventions, surgical splenectomy resulted in immediate and durable resolution of the previously intractable ascites.


Asunto(s)
Malformaciones Arteriovenosas/complicaciones , Ascitis/etiología , Hipertensión Portal/complicaciones , Trasplante de Hígado , Complicaciones Posoperatorias/etiología , Esplenomegalia/complicaciones , Adulto , Humanos , Masculino , Persona de Mediana Edad , Páncreas/anomalías , Páncreas/irrigación sanguínea
4.
Arq. bras. med. vet. zootec ; 64(1): 192-197, Feb. 2012. tab
Artículo en Inglés | LILACS | ID: lil-617947

RESUMEN

The performance of Nile tilapia (Oreochromis niloticus) raised in cages furnished with an automatic dispenser, supplied at different frequencies (once per hour and once every two hours) and periods (daytime, nighttime and both) was evaluated. Eighteen 1.0m³ cages were placed into a 2000m² pond, two meters deep with a 5 percent water exchange. One hundred and seventy tilapias, with initial weight of 16.0±4.9g, were dispersed into each 1m³ cage and the feed ration was adjusted every 21 days with biometry. Data was collected from March to July (autumn and winter). Significant difference to final weight (P<0.05) among treatments was observed. The increase in feeding frequency improves the productive performance of Nile tilapias in cages and permitted better management of the food. The better feed conversion rate for high feeding frequency (24 times day-1) can result in saving up to 360kg of food for each ton of fish produced, increasing the economic sustenance for tilapia culture and suggesting less environmental pollution.


Avaliou-se o desempenho de tilápias-do-nilo (Oreochromis niloticus) produzidas em tanque-rede, providas de dispensadores automáticos de ração, alimentadas em diferentes frequências - uma vez por hora e a cada duas horas - e períodos - durante o dia, à noite ou ambos. Dezoito tanques-rede de 1.0m³ foram colocados em um tanque de 2000m² com dois metros de profundidade e renovação de água de 5 por cento. Cento e setenta tilápias, com peso inicial de 16.0±4.9g foram distribuídas em cada tanque-rede de 1m³ e a taxa alimentar foi ajustada a cada 21 dias junto com as biometrias. As medidas foram coletadas de março a julho (outono e inverno). Observou-se diferença significativa para peso final (P<0.05) entre os tratamentos. O aumento da frequência alimentar melhorou o desempenho produtivo de tilápias-do-nilo produzidas em tanque-rede e permitiu melhor manejo alimentar. A melhor conversão alimentar para alta frequência, 24 vezes dia-1, pode resultar em uma economia de até 360kg de ração por tonelada de peixe produzido, melhorando a sustentabilidade econômica para produção de tilápia e sugerindo menor poluição ambiental.

5.
Environ Sci Technol ; 43(7): 2431-6, 2009 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-19452897

RESUMEN

The Earth's troposphere contains approximately 160 Tg H2 with an average surface mixing ratio approximately 530 nmole mole(-1) (ppb) and lifetime of 2 years. Atmospheric H2 is typically measured using gas chromatography (GC) followed by hot mercuric oxide reduction detection (GC-HgO). Here we describe an alternate method using GC with a pulsed-discharge helium ionization detector (HePPD). HePPD is a universal detector; when applied to H2, the GC-HePDD provides a wide linear range (0.3% over a range of 2000 ppb), a detection limit of approximately 0.03 pg, high precision (0.12%) and a stable response (+/-1.6% over nearly one year). HePPD is compared to HgO reduction using a suite of gravimetrically prepared reference gases spanning remote to urban concentrations. The method is excellent for atmospheric measurements as it provides a wide linear range with high precision, stability and reproducibility. We suggest these characteristics will improve the ability to maintain reference gases and improve measurements of atmospheric H2, thus providing better constraints on potential future changes in its sources and sinks.


Asunto(s)
Atmósfera , Cromatografía de Gases/métodos , Helio/química , Hidrógeno/análisis
6.
Clin Microbiol Infect ; 9(1): 1-14, 2003 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-12691538

RESUMEN

A small armentarium of anti-influenza drugs now exists, and includes the M2 blockers (amantadine and rimantadine) and the neuraminidase inhibitors (Relenza and Tamiflu). The neuraminidase inhibitors have certain advantages, including a broader spectrum of antiviral activity, including influenza A and B viruses. On the other hand, there is now much clinical experience with the M2 blockers, and these drugs are inexpensive. It is clear that influenza in different community groups needs to be managed in specific and targeted ways. For example, in the over-65-years and at-risk groups, vaccination will remain a mainstay of disease prevention. However, up to 40% of those in these groups may fail to receive vaccine, and therefore the antivirals can be used therapeutically, or, in defined circumstances, as prophylactics. At present, influenza is hardly managed in the community. The infrequent global outbreaks, pandemics, present further problems. The more extensive use of the two classes of antivirals, and also vaccines, in the important interpandemic years will provide a very significant investment in health benefits in the face of a new pandemic virus in an otherwise completely vulnerable population.


Asunto(s)
Antivirales/uso terapéutico , Brotes de Enfermedades , Enfermedades Endémicas , Inhibidores Enzimáticos/uso terapéutico , Gripe Humana/tratamiento farmacológico , Neuraminidasa/antagonistas & inhibidores , Proteínas de la Matriz Viral/antagonistas & inhibidores , Acetamidas/uso terapéutico , Amantadina/uso terapéutico , Ensayos Clínicos como Asunto , Guanidinas , Humanos , Gripe Humana/epidemiología , Oseltamivir , Piranos , Rimantadina/uso terapéutico , Ácidos Siálicos/uso terapéutico , Zanamivir
7.
AIDS Res Hum Retroviruses ; 18(1): 85-8, 2002 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-11804560

RESUMEN

Here we report the construction, sequencing, and biological characterization of a molecular clone of HIV-1(92UG001), a virus representative of subtype D strains circulating in Uganda. The virus produced by the clone has an aggressive syncytium-inducing phenotype, which matches that of the parental virus. This phenotype may be related to duplication of a binding site for a transcription factor, T cell factor 1alpha (TCF-1alpha), in the long terminal repeat of the virus.


Asunto(s)
Genoma Viral , Infecciones por VIH/virología , VIH-1/genética , Adulto , Secuencia de Bases , Sitios de Unión , Clonación Molecular , Proteínas de Unión al ADN/metabolismo , Células Gigantes/virología , Infecciones por VIH/epidemiología , Duplicado del Terminal Largo de VIH , VIH-1/aislamiento & purificación , Humanos , Leucocitos Mononucleares/virología , Factor de Unión 1 al Potenciador Linfoide , Masculino , Datos de Secuencia Molecular , Fenotipo , Factores de Transcripción/metabolismo , Uganda/epidemiología
10.
AIDS Res Hum Retroviruses ; 16(12): 1175-8, 2000 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-10954893

RESUMEN

Here we report the construction, sequencing, and repair of a molecular clone of HIV-1GB8, a virus representative of HIV-1 subtype B strains circulating in the UK. The phenotype of virus produced by the clone matches that of the parental virus. The molecular clone will be used in the production of attenuated virus stocks for chemical inactivation to allow development of faccines based on killed whole virus preparations.


Asunto(s)
VIH-1/clasificación , VIH-1/genética , Filogenia , Secuencia de Bases , Clonación Molecular , VIH-1/aislamiento & purificación , Humanos , Datos de Secuencia Molecular , Reino Unido
11.
Surg Neurol ; 50(1): 73-6, 1998 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9657496

RESUMEN

BACKGROUND: Subtemporal decompression, first advocated by Dandy for the treatment of benign intracranial hypertension or pseudotumor cerebri, has been replaced as a treatment mainstay by medical management using diuretics, steroids, and lumbar puncture. Failure of these forms of treatment has frequently led to insertion of cerebrospinal fluid shunts. METHODS: We have retrospectively reviewed the long term outcome of eight patients who were treated by subtemporal decompression (STD) for classical presentations of refractory benign intracranial hypertension. The follow-up period ranged from 8 to 26 years. RESULTS: Within 1 month of STD, deterioration in visual fields and acuity resolved in all eight patients. Five of eight patients required CSF diversion procedures after subtemporal decompression to control headaches. No patient experienced recurrent permanent visual deterioration after STD. CONCLUSION: STD may be the most effective treatment in both long and short term follow-up to provide lasting relief and prevention of visual morbidity caused by refractory benign intracranial hypertension.


Asunto(s)
Descompresión Quirúrgica , Hipertensión Intracraneal/cirugía , Adolescente , Adulto , Derivaciones del Líquido Cefalorraquídeo , Niño , Descompresión Quirúrgica/métodos , Estudios de Seguimiento , Cefalea/etiología , Humanos , Hipertensión Intracraneal/complicaciones , Hipertensión Intracraneal/etiología , Estudios Retrospectivos , Resultado del Tratamiento , Trastornos de la Visión/etiología , Agudeza Visual
13.
Pediatr Neurosurg ; 26(6): 322-5, 1997 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9485161

RESUMEN

Modern neuroimaging techniques have led to increased identification of angiographically occult cerebral angiomatous malformations. Cavernous angiomas or cavernomas account for approximately 16% of all cerebrovascular malformations. Little is reported about the etiology or risk for acquiring these lesions. This report suggests a possible association between acquired intracranial vascular malformations and long-term survivors after craniospinal external beam radiation therapy indicating that greater understanding of the cerebral vascular system's response to injury may provide insight into the evolution and progression of these lesions.


Asunto(s)
Neoplasias Encefálicas/etiología , Neoplasias Encefálicas/radioterapia , Neoplasias Cerebelosas/radioterapia , Ependimoma/radioterapia , Hemangioma Cavernoso/etiología , Meduloblastoma/radioterapia , Neoplasias Inducidas por Radiación , Neoplasias Primarias Secundarias , Adolescente , Neoplasias Encefálicas/diagnóstico , Ventrículos Cerebrales , Preescolar , Irradiación Craneana/efectos adversos , Hemangioma Cavernoso/diagnóstico , Hemangioma Cavernoso/patología , Humanos , Masculino , Microcirculación/efectos de la radiación , Lóbulo Parietal , Sobrevivientes , Lóbulo Temporal
14.
Pediatr Neurosurg ; 26(4): 197-9, 1997 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9436830

RESUMEN

Six patients with hydrocephalus who were treated with cerebrospinal fluid (CSF) shunts became refractory to serosal absorption of CSF. All were subsequently treated with ventriculo-gallbladder shunts. The surgical technique and long-term results were evaluated by retrospective review of the hospital records. Detailed evaluation of 1 of the 6 has suggested a dynamic role for the gallbladder in the function of ventriculo-gallbladder shunts.


Asunto(s)
Derivaciones del Líquido Cefalorraquídeo/métodos , Vesícula Biliar/fisiología , Hidrocefalia/cirugía , Humanos , Estudios Retrospectivos
15.
Fertil Steril ; 68(6): 987-91, 1997 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9418684

RESUMEN

OBJECTIVE: To evaluate the sensitivity of GH secretion to the suppressive effect of oral glucose administration in women with polycystic ovary syndrome (PCOS). DESIGN: Comparison of the GH response to an oral glucose load in women with PCOS and in weight-matched normally menstruating women (controls). SETTING: Reproductive endocrinology unit. PATIENT(S): Eighteen obese and 11 nonobese patients and 10 obese and 10 nonobese controls. INTERVENTION(S): After an overnight fast, each woman underwent a 75-g, 3-hour oral glucose tolerance test (OGTT). MEAN OUTCOME MEASURE(S): Growth hormone, glucose, and insulin responses to OGTT. RESULT(S): No significant differences in the glycemic and insulinemic responses were found between the patients and the weight-matched controls. No decrease in plasma GH was observed in both obese and nonobese patients and in obese controls during the OGTT, whereas a significant GH decrease occurred in nonobese controls 60 and 120 minutes after glucose intake. CONCLUSION(S): Oral glucose administration was unable to suppress GH levels in nonobese as well as in obese women with PCOS and in obese control women. These data suggest that both PCOS and obesity are associated with a reduced sensitivity of GH secretion to glucose suppression.


Asunto(s)
Glucosa/farmacología , Hormona del Crecimiento/sangre , Hormona del Crecimiento/efectos de los fármacos , Obesidad/sangre , Síndrome del Ovario Poliquístico/sangre , Síndrome del Ovario Poliquístico/tratamiento farmacológico , Administración Oral , Adulto , Estudios de Casos y Controles , Femenino , Glucosa/administración & dosificación , Prueba de Tolerancia a la Glucosa , Humanos , Obesidad/etiología , Síndrome del Ovario Poliquístico/complicaciones , Factores de Tiempo
16.
Hum Mol Genet ; 3(10): 1873-6, 1994 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-7849715

RESUMEN

Fourteen Caucasian families with 81 affected individuals have been assessed in which polycystic ovaries/male pattern baldness (PCO/MPB) segregates as an autosomal dominant phenotype (1). The gene CYP17, coding for P450c17 alpha (17 alpha-hydroxylase; 17/20 lyase) on chromosome 10q24.3 is the rate-limiting step in androgen biosynthesis. We have identified a new single base change in the 5' promoter region of CYP17 by heteroduplex analysis. This creates an additional SP1-type (CCACC box) promoter site, which may cause increased expression. This base change also creates a recognition site for the restriction enzyme MspA1 allowing a simple screening procedure. There is a significant association between the presence of this base change (A2) and the affected state for consecutively identified Caucasian women with PCO as compared either to consecutively matched controls (P = 0.03) with an odds ratio for those with at least one A2 allele of 3.57, or to a random population (P = 0.02) with an odds ratio of 2.50. Within the fourteen families, members with PCO or MPB have a significant association with the occurrence of at least one A2 allele compared to their normal relatives, with an odds ratio of 2.20 (P = 0.05). The base change does not cosegregate with the affected phenotype within the families showing association, demonstrating that this mutation of CYP17 does not cause PCO/MPB. Variation in the A2 allele of the CYP17 gene is a significant factor modifying the expression of PCO/MPB in families where it has been demonstrated to segregate as a single gene disorder, but it is excluded as the primary genetic defect.


Asunto(s)
Alopecia/genética , Cromosomas Humanos Par 10 , Mutación Puntual , Síndrome del Ovario Poliquístico/genética , Esteroide 17-alfa-Hidroxilasa/genética , Alelos , Alopecia/enzimología , Secuencia de Bases , Mapeo Cromosómico , Cartilla de ADN , Femenino , Humanos , Escala de Lod , Masculino , Datos de Secuencia Molecular , Linaje , Síndrome del Ovario Poliquístico/enzimología , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Regiones Promotoras Genéticas , Distribución Aleatoria , Recombinación Genética
17.
Science ; 263(5153): 1587-90, 1994 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-17744786

RESUMEN

Measurements of carbon monoxide (CO) in air samples collected from 27 locations between 71 degrees N and 41 degrees S show that atmospheric levels of this gas have decreased worldwide over the past 2 to 5 years. During this period, CO decreased at nearly a constant rate in the high northern latitudes. In contrast, in the tropics an abrupt decrease occurred beginning at the end of 1991. In the Northern Hemisphere, CO decreased at a spatially and temporally averaged rate of 7.3 (+/-0.9) parts per billion per year (6.1 percent per year) from June 1990 to June 1993, whereas in the Southern Hemisphere, CO decreased 4.2 (+/-0.5) parts per billion per year (7.0 percent per year). This recent change is opposite a long-term trend of a 1 to 2 percent per year increase inferred from measurements made in the Northern Hemisphere during the past 30 years.

18.
J Urol ; 144(4): 872-4, 1990 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2398561

RESUMEN

From 1987 to 1988 we used cold biopsy forceps to remove completely 92 urothelial neoplasms ranging from 0.3 to 3 mm. Rigid biopsy forceps were used. The urologist usually treats these bladder neoplasms by diathermy coagulation, which obviously makes histological study impossible. On the other hand, due to the small size of these lesions even removal with the cutting loop inevitably causes deep regressive modifications that prevent accurate morphological evaluation. Histological examination of the neoplasms removed revealed the presence of low to medium grade (stage Ta, grades 1 to 2) noninfiltrating papillary carcinoma in 75 cases, high grade (stage Ta, grade 3) noninfiltrating papillary carcinoma in 9 and medium to high grade (stage T1, grades 2 to 3) infiltrating papillary carcinoma in 8, 1 of which had areas of squamous cell carcinoma. This method enabled us to study the morphology of the urothelial lesions in the initial phase. In our study population the number of high grade lesions and/or lesions with early signs of infiltration (17 of 92) appears to be noteworthy despite the small size of the tumors.


Asunto(s)
Carcinoma de Células Transicionales/patología , Carcinoma de Células Transicionales/cirugía , Neoplasias de la Vejiga Urinaria/patología , Neoplasias de la Vejiga Urinaria/cirugía , Biopsia/instrumentación , Cistoscopía , Humanos
20.
Chir Ital ; 39(6): 559-72, 1987 Dec.
Artículo en Italiano | MEDLINE | ID: mdl-3446415

RESUMEN

The authors examine the question of the pathogenesis of solitary rectal ulcer syndrome (S.R.U.S), illustrating the importance of a correct differential diagnosis versus other relevant forms of disease affecting this region, particularly rectal cancer. They describe their experience with both the medical and surgical treatment of the syndrome.


Asunto(s)
Complicaciones Posoperatorias , Enfermedades del Recto/cirugía , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Recurrencia , Reoperación , Úlcera/cirugía
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...